4 3 2 1 VCC E1 VCC 4.35V - 5.5V J1 4 E17 VBUS 1 D- 2 D+ 3 ID 4 GND 5 USB TP1 DTP2 D+ TP3 ID E2 C10 1 10V C1 10 6.3V 0603 LTC3558EUD 20 VCC R1 1.0 5% CHRG E3 16 HPWR 2 PVIN1 7 PVIN2 8 C8 22 6.3V 0805 SW1 100% 20% R16 324K SUSP JP2 SUSP 17 CHARGER ON OFF FB1 R4 100K 0 R5 ENTC INT EXT 0 18 VOUT2 11 SWAB2 9 PROG L2 2.2uH 1072AS-2R2M E6 PROG 2 5 EN1 15 EN2 EN1 JP4 EN1 OFF BAT R7 1.0M 3 SWCD2 10 MODE 21 FB2 13 VC2 GND 14 1 OFF 1 ON E9 330pF 15k R11 105k C2 10pF MODE E10 GND JP6 MODE 0 R9 1.0M 1 LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. 3 MODE 1 0 JP6 settings BUCK BUCK-BOOST BURST BURST PULSE SKIP PWM Unless noted: Resistors: Ohms, 0402, 1%, 1/16W Capacitors: uF, 0402, 10%, 50V CONTRACT NO. APPROVALS TECHNOLOGY DRAWN: G. Barbehenn CHECKED: TITLE: 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 LTC Confidential-For Customer Use Only SCHEMATIC LTC3558EUD: Linear USB Battery Charger with Buck and Buck-Boost Regulators APPROVED: ENGINEER: G. Barbehenn SIZE DESIGNER: A THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 4 E11 GND 2 R10 CUSTOMER NOTICE E12 VOUT2 3.3V 400mA R13 121k EN2 R8 1.0M 3 TP4 E8 JP5 EN2 GND C4 33pF R12 324k C3 GND ON E13 C5 22 6.3V 0805 R14 20 5% R6 1.74K E7 C7 10 6.3V 0603 R15 649K R2 100K JP3 NTC C6 22pF 4 NTC E5 R3 E15 GND E14 VOUT1 1.2V 400mA 6 1098AS-4R7M 12 BAT GND ENTC DF3-3P-2DSA ENTC L1 4.7uH E4 NTC R17 1.0 5% 1 2 3 4 HPWR JP1 HPWR 3 E16 BAT FLOAT=4.2V 0.5A J2 OPT C9 4.7 6.3V 0603 19 BAT CHRG BAT R18 1k 5% 0603 U1 GND SUSP D1 CHRG GREEN DATE: 2 DWG NO. REV DC1276B B SHEET 1 Friday, February 08, 2008 1 OF 1 1